CDB_Connection*
CDBConnectionFactory::MakeDBConnection(
I_DriverContext& ctx,
const CDBConnParams& params)
{
CFastMutexGuard mg(m_Mtx);
CDB_UserHandler::ClearExceptions(m_Errors);
CDB_Connection* t_con = NULL;
CRuntimeData& rt_data = GetRuntimeData(params.GetConnValidator());
TSvrRef dsp_srv = rt_data.GetDispatchedServer(params.GetServerName());
// Prepare to collect messages, whose proper severity depends on whether
// ANY attempt succeeds.
impl::CDBHandlerStack ultimate_handlers;
{{
const impl::CDriverContext* ctx_impl
= dynamic_cast<impl::CDriverContext*>(&ctx);
if (params.GetOpeningMsgHandlers().GetSize() > 0) {
ultimate_handlers = params.GetOpeningMsgHandlers();
} else if (ctx_impl != NULL) {
ultimate_handlers = ctx_impl->GetCtxHandlerStack();
} else {
ultimate_handlers.Push(&CDB_UserHandler::GetDefault());
}
}}
SOpeningContext opening_ctx(ctx);
CRef<CDB_UserHandler_Deferred> handler
(new CDB_UserHandler_Deferred(ultimate_handlers));
opening_ctx.handlers.Push(&*handler, eTakeOwnership);
// Store original query timeout ...
unsigned int query_timeout = ctx.GetTimeout();
// Set "validation timeouts" ...
ctx.SetTimeout(CalculateConnectionTimeout(ctx));
ctx.SetLoginTimeout(CalculateLoginTimeout(ctx));
if ( dsp_srv.Empty() ) {
// We are here either because server name was never dispatched or
// because a named connection pool has been used before.
// Dispatch server name ...
t_con = DispatchServerName(opening_ctx, params);
} else {
// Server name is already dispatched ...
string single_server(params.GetParam("single_server"));
// We probably need to re-dispatch it ...
if (single_server != "true" && GetMaxNumOfDispatches() &&
rt_data.GetNumOfDispatches(params.GetServerName()) >= GetMaxNumOfDispatches()) {
// We definitely need to re-dispatch it ...
// Clean previous info ...
rt_data.SetDispatchedServer(params.GetServerName(), TSvrRef());
t_con = DispatchServerName(opening_ctx, params);
} else {
// We do not need to re-dispatch it ...
// Try to connect.
try {
// I_DriverContext::SConnAttr cur_conn_attr(conn_attr);
// cur_conn_attr.srv_name = dsp_srv->GetName();
CDB_DBLB_Delegate cur_params(
dsp_srv->GetName(),
dsp_srv->GetHost(),
dsp_srv->GetPort(),
params);
cur_params.SetOpeningMsgHandlers() = opening_ctx.handlers;
// MakeValidConnection may return NULL here because a newly
// created connection may not pass validation.
t_con = MakeValidConnection(opening_ctx,
// cur_conn_attr,
cur_params);
} catch (CDB_Exception& ex) {
// m_Errors.push_back(ex.Clone());
opening_ctx.handlers.PostMsg(&ex);
if (params.GetConnValidator()) {
opening_ctx.conn_status
= params.GetConnValidator()->ValidateException(ex);
}
}
if (!t_con) {
// We couldn't connect ...
if (single_server != "true") {
// Server might be temporarily unavailable ...
// Check conn_status ...
if (opening_ctx.conn_status
== IConnValidator::eTempInvalidConn) {
rt_data.IncNumOfValidationFailures(params.GetServerName(),
dsp_srv);
}
// Re-dispatch ...
t_con = DispatchServerName(opening_ctx, params);
}
} else {
// Dispatched server is already set, but calling of this method
// will increase number of successful dispatches.
rt_data.SetDispatchedServer(params.GetServerName(), dsp_srv);
}
}
}
// Restore original connection timeout ...
ctx.SetTimeout(query_timeout);
// Restore original query timeout ...
if (t_con) {
t_con->SetTimeout(query_timeout);
}
x_LogConnection(opening_ctx, t_con, params);
handler->Flush((t_con == NULL) ? eDiagSevMax : eDiag_Warning);
return t_con;
}
